199647661851 has 24 divisors (see below), whose sum is σ = 315087205680. Its totient is φ = 120809779200.

The previous prime is 199647661817. The next prime is 199647661877. The reversal of 199647661851 is 158166746991.

199647661851 is a `hidden beast` number, since 1 + 9 + 9 + 6 + 4 + 7 + 6 + 618 + 5 + 1 = 666.

It is not a de Polignac number, because 199647661851 - 2¹⁰ = 199647660827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (199647661891) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1509586 + ... + 1636503.

It is an arithmetic number, because the mean of its divisors is an integer number (13128633570).

Almost surely, 2^199647661851 is an apocalyptic number.

199647661851 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

199647661851 is a deficient number, since it is larger than the sum of its proper divisors (115439543829).

199647661851 is a wasteful number, since it uses less digits than its factorization.

199647661851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3146747 (or 3146744 counting only the distinct ones).

The product of its digits is 19595520, while the sum is 63.

The spelling of 199647661851 in words is "one hundred ninety-nine billion, six hundred forty-seven million, six hundred sixty-one thousand, eight hundred fifty-one".